/Engine/Plugins/Online/OnlineSubsystemUtils/Source/OnlineSubsystemUtils/Public/SpectatorBeaconHost.h
Delegate called when the beacon gets any request, allowing the owner to validate players at a higher level (bans,etc)
typedef TBaseDelegate_OneParam< bool, const [FPlayerReservation](API\Plugins\OnlineSubsystemUtils\FPlayerReservation) & > FOnSpectatorValidatePlayers